VOLVO
ECM-988A - Engine control module (ECM). Internal fault. Intermittent fault
System
Engine Control Module (ECM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (5)
- Volvo S60 (2001–2009)2004Engine B5204T5, B5234T3, B5234T7, B5254T2, B5254T4 only
- Volvo S80 (1999–2006)2004Engine B5204T5, B5234T7, B5254T2, B6294S2, B6294T only
- Volvo V70 (2000–2008)2004Engine B5204T5, B5234T3, B5234T7, B5254T2, B5254T4 only
- Volvo V70 XC / XC70 (2001–2007)2004All engines except: D5244T
- Volvo XC90 (2003–)2004All engines except: D5244T
What does this fault code mean?
The engine control module (ECM) registered a fault on an earlier occasion, but it no longer detects the fault now. The code therefore refers to an intermittent internal fault in the module. While the fault was present, engine speed and torque were limited and the cruise control was switched off.
Possible causes
- Defective engine control module (ECM)
What you can do
- 1Read the code and clear it, then road test the car to see whether it returns
- 2Check that the battery is in good condition and that the engine control module connectors are fully seated; if anything is loose, secure it and road test again
- 3If the code returns, the engine control module is probably what needs replacing, and a workshop should do this
Symptoms you may notice4
- Maximum engine speed is lower than normal
- Cruise control is switched off
- Uneven idle
- Malfunction indicator lamp (MIL) is on
What the fault can affect1
- Engine speed and torque are capped at a level the module calculates as normal
General guidance for car owners. Diagnosis on the car can point to a different cause.